I configured our database to handle both shared server requests and dedicated server requests. Is there a way on the server end to make sure that incoming client requests default to connecting to a dedicated server?

Right now the only way I know how to do this is to specify on the tnsnames.ora file of the client machine (SERVER=DEDICATED) for the tnsnames.ora's definition for our database, but there's got to be a way to do it on the server end.

If you want to force every incoming connection to use a dedicated server then set the parameter USE_DEDICATED_SERVER=ON in your sqlnet.ora file of your clients. This will force the listener to spawn a dedicated server for all network sessions. It does this by adding (SERVER=dedicated) to the CONNECT_DATA section of connect descriptors. Connections from your clients will be given dedicated servers, even if shared server is configured on server side.